Non-oscillating, non-steerable parachute



.A. ISTEL arm. 2,925971 LE PARAC I United States Patent NON-OSCILLATING, NON-STEERABLE PARACHUTE Application August 5, 1957, Serial N0. 676,176

6 Claims. (C1. 244-145) This invention melates to parachutes. More specifical- 1y, it pertains to non-oscillating, non-steerable parachutes for Student use.

In recent years, parachuting has advanced from the status of beign solely a life-saving 01' an exhi-bition art to that of a world-wide competitive sport. Mo'st countries of the world now have, 01' are in the process of forming, parachuting clubs or teams; parachuting competition is encouraged on both national and international levels. As a result of the increasing interest in spart paraehuting, many governments and other interested parties have felt it necessary that rules and regulations be forrned to govern the sport. Foremost among such regulations would be rules directed to the procedure followed in teaching students to jump. These aregulations must be supplemented by equipment which has been specifically designed for the protection of the student jnmper.

During the last half century, parachutes and parachuting equipment have undergone vast improvements. The present-day parachutes are now provided with many varied forms of safety features and are extremely dependable. In conjunction with the safety improvements, the parachute has undergone radical changes which aflect the descent of the chute and the ability of the chutist to control the same. The present-day jumper, -by merely manipulating the shroud lines of his parachute, can coutrol his rate of descent, the speed of his forward momenturn and the direction in which such descent is made. Such advances in parachuting technology are evidenced by the efliciency of military parachuting and the accuracy of oompetitive sport jumpers. v

The parachutes, which form the basic equipment of the modern jumper, eifectively serve military, exhibit-ion and sport pumping pumposes, -bnt do not fulfill the needs of the novice jumper. Those parties who are interested in promoting sport jumping and in regulating the teaching of the art believe it is extremely desirable to fully coutrol the novice in his early jumps. It is, of course, obvious that the instructor cannot control the student jumper when he has the ability to steer or control the descent of his own parachute. The modern parachutes, as aforementioned, are steerable and therefore are unsatisfactory for use in teaching. Steerable parachutes, as that term is used in this specification, refers to parachutes which may be controlled-with respect to forward direction, but does not refer to rotatability. The elimination of the students ability to control the descent of his own parachute might be aceomplished by reverting to the earlier type, non-steerable, parachutes, but such action would raise an equally, if not more, -diflicult problem. The early parachutes had the tendency to oscillate dnring descent to such a degree that the jumpers ability to malte a Safe landing was greatly inhibited. Thus, with the obstacles of steerability and oscillation barring the way to safe parachute instruction, it has become evident that a new form of parachute is necessary.

. This inventionprovides the requ-ired parachute and eliminates the problems aforementioned. By means of a redesigned canopy, a non-oscillating, non-steerable parachute -is provided. It is, therefore, an object of this inventioxi to provide a non-steerable parachute. It is also an object of the invention to provide a parachute which will not oscillate during descent.

' With this and other objects in mind, reference is had to the attached sheet 'of drawings, illustrating one form of the invention, wherein like characters represent.like parts, and in which: 1

Fig. 1'is a perspective view of the parachute of invention in inflated condition; and

Fig. 2 is a top plan view of the vention in inflated condition The oscillation of the parachute and parachute steer ability are directly related to the action between the canopy and the air column down which the canopy descends. In descent, a paraehute, much like an elevator, rides down a predeterrnined channel which is defined by the c0lumn of air directly beneath the canopy. It is, of course, obvious that -as the parachute deseends, the Column of air is compressed beneath the canopy. Such compression acts to spill the air out of the canopy around its peripheral edge. If more air spills from one side of the canopy than the other, the parachute tends to swing in that direction; this swing is known as oscillation. In general parachuting practice, the oscillation aforedescribed is -dampened by vigorously pulling down on the shroud lines on the high side oi spilling side cf the parachute as the body swings in that direction. As soon as the body starts its return swing, the shroud lines are reieased and the swing in the other directio n is met by pulling down 011 the opposite shroud lines as the body Comes up on that side. It should here be noted, that oscillation is extremely dangerous when the parachute -is close to the ground and the difliculties in dampening such oscillation are increased mmyfold. Therefore, the tendency to oscillate must be decreased as much as possible for the noviee jumper.

It has been found that a parachute may be steered paraehute cf this or eontrolled in descent by substantially simulating that which occurs during the oscillation of the parachute. If the jumper wishes the parachute to move to his 1'ight, he puils down on the shroud lines at his right in such a manner that the air is spilled from the canopy at his left-hand side, such spilling causing the paraehute to slip or move to the i'ight. Conversely, movement to the left can be -accomplished by pulling down 011 the left-hand shroud lines to spill the air from the right side cf the canopy.

Steerability should not be confused with the -rotatability of: a parachute. It 1's highly desi-rable that a jumper, =be he ex;' erienced or novice, be able to fce in the direction in which he is landing. In order .to accornplish this, the jumper must be able to rotate his parachute at will.

It should at this point be noted that a portion of the air cornpressed beneath the canopy ismeleased therethrough by means of a puckered vent at the apex of the canopy. The release of this air tends to stabilize the parachute to a small degree and acts to prevent a rending of the parachute material er extremely violent oscillation Further, a small percentage of the air cont-ained within the canopy is permitted to pass through the canopy material. The amount of air which passes through the canopy material is dependent on the porosity of the material, the porosity being measured in cubic feet per squate foot per minute. The velocity of the parachutes descent is related to the porosity of the canopy and the amount of air which is vented or spilled therefrom.

The parachute of the instant invention, by means ofan 3. lation and prevents the jumpr fi'0rn controlling h'1s lirection f descent. Further, the improved canopy mcreases the rotatability 0f the parachute.

Refer ring now 1;0 .the drawings, a canqpy, generally indicated by 'the ,numeir'al 30 is show n. The canPY 30, {vl1i0h niay conveniently'be' silk, nyl0n 0r pongee 111aterial, compriss a plurality of panels or gores 31. Bach 0f tl1e gores form a radial segment of the canopy and am secuied together by reinf orced sea ms indicated by the numerals 1 through 28. In the language 0f the parachuting art, each 0f the gores or panels 31 is identified and located with respect t0 the jumper by the sea.ms definir1g the edges 0f the gores. Thns, the panel a1; the jumpers rear is defined as gore 1- -28 while the panel tthe jumpers front is d efined as gore 1415. The base portion 013 the panels 31 define the sl irt 01 outer- 1110st edge 32 cf the canopy, said edge being reinforced by any means known t0 the art. The apex of the panels 31 define the circumference cf the apex 0r puckered vent 33 of the canopy which may be formed in any manner comn1on t0 the art. In general practice, the puckered vent is provided with a circumferential, reinforced sean1 having housed therein a rubber 01' 0ther flexible ring which is adapted to expand 01 contract t0 perrnit the venting 015 air from the canopy. Shroud lines 34 extend throughthe center of the pu0kered vent 33 outwardly 0f the canopy 30, at opposite sides thereof, through seams 1 t 0 28 for connection t0 risers 35. Tl1e shroud lines, by regulation, must extend uninterruptedly fr0m a riser 0n 01ie side of the canopy thl'0llgh the canopy t0 a riser on its opposite side. The shoud lines are seoured to the risers 35 by means 0f connector links 36. In comrn0n practice, an equal nun1ber of shoud lines is secured t0 each riser strap. In the embodiment of: the invention shown, there are 28 sh.roud lines, 7 secured t0 each 0f the risers 35. The risers 35 f0rm part, 01' are secured to, a hamess or 0ther load-carrying device (not shown).

lt is worthy of note that we ha.ve found it desirable t0 utilize can0py material having a porosity 0f ab0ut 50 cubic feet per square foot per minute; materials 0f this porosity tend t0 c0-act with the venting means t0 be hereinafter described to slow the descent of the parachute and facilitate the operation thereof.

Four venting slits 37 have been provided in the canopy 30, one adjacent and parallel t0 each of the seams 4, '11, 18 and 25. lt has been found desirable to provide the slits alternately 011 opposite sides of the seams. Thus, the venting slits 37 located respectively in gores 45 and 18-19 are 011 the Same side of their associated seams, whereas venting Slits 37 in gores 11 and 2425, respectively, are located 0n the opposite side 0f their associated searns. The vents 37, which are merely cuts in the canopy material, are reinforced by tape 0r in any other manner known to the art and extend f1'0m the skirt 32 radially inwardly toward the apex 015 the canopy. The inner and of the vent 37 is meinforced to prevent extensi0n of the slit by a reinforcing tape 38 extending transversely of the slit. It should here be noted that the venting slits 37 are positioned at appr0ximately 45 angles fr0n 1 the jun1pers f.r0nt and rear, and that they extend substantially half the distance from the skirt to the apex of the canopy. It has been found that slits from 6 feet t0 8 feet in length are most elfective with a canopy having a 28-f00t diameter.

In operation, the can0py 0f this invention dampens oscillation and provides for a more stable descent by equalizing the venting 0f the air therefrom. Slits 37 act 10 vent the air such that it is not spilled from the can0py axou nd it periphery 01' skirt edge 32.

With respect 10 the nonsteerable features of the parachute, we have f0und the explanation more diflficult. It is ou1' belief that the parachute formed with the instant canopy is non-steerable in that jurnpers pulling downwardly 0n the rigl1t-hand shroud lines, t0 move t0 the right, opehs the venti ng, sli1;s 37 at bis left to permit -th g:

escape of the air therefrom, instead of spilling the air from tl1at side of the canopy. In tl1is manner, the air trapped within the canopy is permitted t0 escape upwardly thxough the venting slits 37, instead 0f spilling downwardly around the peripheral edge 0f the canopy, which downward movement would normally raise the side of the canopy and cause the parachute to m0ve in the opposite direction. It is, of c0urse, obvious that a downward pull 011 the shroud lines on any side of the canopy would tencl to open the venting slits 011 the opposite side thereof and thus prevent a change in directional movernent.

lt has been found that the improvement in canopies, as above described, increases the rotatability of the parachute. Slow rotation t0 the right may be accomplished by pulling downwardly 0n the right rear riser and rotati0n 0f increased speed is aeeomplished by pulling down- Wardly on the 1'ight rear and left fr0nt risers simultaneously. Thus, in the first instance venting slit 37, f0rmed in g0re 2425, will be forced into a closed posi ti0n, while in the second instance this venting slit, as well as the venting slit f0rrned in g0re 1011, will be cl0sed. The downward pull 0n the .risers tends t0 close the related vents, thus permitting the air deflection 0f the vents which rernain 0pen t0 turn the parachute. Natu rally, vari0us degrees 0f rotation are possible depending upon the extent 0f closing of the actuated venting slits- 37. It is, of course, 0bvi0us that the parachute may be rotated t0 the left -by a downward pull 011 the left rear and right front risers. In this connection, venting slits 37 disposed in gores 45 and 18-19, respectively, will be actuated towards a closed position. By means 0f the increased rotatability cf the parachute, a jumper may quickly turn to face in the direction in which he is landing. Thus, am0ng others, the several objects of the invention as aforenoted are achieved. Obviously, numerous changes in construction may be resorted t0 without departing from the spirit 0f the invention as clefined by the claims.

We claim:

1. A non-oscillating, non-steerable and selectively rotatable parachute including a gored canopy being provided with four substantially evenly spaced venting slits, adjacent gores being separated by seams, said Slits extending radially inwardly between the periphery 0f said canopy and the apex thereof, and each 0f said slits being adjacent one 0f said searns, and each of said slits being 011 the opposed side 0f 1'ts adjacent seam relative t0 the two'adjacent slits spaced therefrom in either Cil'6llfth ferentially extending di1ection.

2. A non-0scillating, non-steerable parachute as in claim l, wherein said venting slits are 0f a length equal t0 substantially half the distance between the periphery 0f said canopy and the apex there0f.

3. A non-oscillating, non-steerable parachute as in claim 1, wherein said canopy possesses approximately a twenty-eight foot diameter and wherein said venting slits are between ap;1roximately six t0 eight feet in length.

4. A non-oscillatiug, non-steerable parachute as in claim l, wherein said canopy has a p0r0sity of about fifty cubic feet per square foot per minute.

5. A non-oscillating, non-steerable and selectively ro tatable parachute includinfg, in combination, a l0aclcarrying harness, shroud lines secured to said harness. and a canopy, said can0py comprising a plurality of radially extending panels secured one t0 another, said shroud lines extending between said pancls through said ean0py and the apex there0f, and a plux'ality 0f evenly spaced radially extending venting slits formed in certain 0f said panels between the periphery and apex 0f said can0py, each of said slits being adjacent t0 and parallel t0 one of said shroud lines and adjacent slits being on opposed sides of their adjacent shr0ud lines.

6. A non-oscillating, non-steerable and selectively 1'0- tatable parachute including a g0red canopy with adjacent g01'es separated I;y a sea1n, said canppy being provided References Cited in the file of this patent UNITED STATES PATENTS 1733732 Henvis -i Oct. 29', 1929 6 Mahner Oct. 7, 1930 Tricau Inne 7, 1932 Sedlmayr May 31, 1938 Derry Sept. 4, 1945 Maggi Oct. 4, 1949 OTHER REFERENCES 10 Parachutcs, by W. D. Brown, published 1951. published by Sir Isaac Pitman & Suns, Ltd., London; chapter 6, pages 55 thxough 58. inclusive. 

